"We have to deal with family members who are trying to grapple with it. And sometimes people are not sensitive, including the Malaysian government, including MAS."

He insisted the Chinese relatives who demonstrated outside the Malaysian Embassy in Beijing, and then later in Kuala Lumpur, did not represent all the family members:

"I know there are families who are really not happy with how things are going and we try to manage it," he said.

"But at the same time there is also the other side of the coin where other people have been dealing with their grief in a different way."

Video:New Possible Plane 'Ping' Detected

"I can only do my best. I can only tell you what I know. But the problem with the families is that the one question they want to know I don't have the answers to just yet, which is: Where are their loved ones? Where is the plane?"

It remains unclear who will take possession of the black box once it is found.

It could be the Malaysian government, the American National Transportation Board, British Air Accident Investigations Branch, or perhaps a multi-national group.

But the belief is that the Australians have found the location of the missing plane, although they are yet to retrieve any wreckage.

"I think it is the black box and I hope it is the black box, but if not I will still not give up," Mr Hussein said.